Error 500: Bubbling failed.

Overview

I'm getting an error "An unexpected error has occurred while fetching components. Error 500: Bubbling failed." when in the editor and trying to load components.

I cannot recover from this. I've tried

• Clearing cache
• Creating a new Canvas page

I haven't changed any code. However I did this (not sure how), I did it via the UI... but I do not have the exact steps I took to get to this error.

Here's the stack trace from watchdog:

AssertionError: Bubbling failed. in assert() (line 623 of /var/www/html/web/core/lib/Drupal/Core/Render/Renderer.php).

#0 /var/www/html/web/core/lib/Drupal/Core/Render/Renderer.php(623): assert()
#1 /var/www/html/web/modules/contrib/canvas/src/Element/RenderSafeComponentContainer.php(59): Drupal\Core\Render\Renderer->executeInRenderContext()
#2 [internal function]: Drupal\canvas\Element\RenderSafeComponentContainer->renderComponent()
#3 /var/www/html/web/core/lib/Drupal/Core/Security/DoTrustedCallbackTrait.php(107): call_user_func_array()
#4 /var/www/html/web/core/lib/Drupal/Core/Render/Renderer.php(871): Drupal\Core\Render\Renderer->doTrustedCallback()
#5 /var/www/html/web/core/lib/Drupal/Core/Render/Renderer.php(433): Drupal\Core\Render\Renderer->doCallback()
#6 /var/www/html/web/core/lib/Drupal/Core/Render/Renderer.php(245): Drupal\Core\Render\Renderer->doRender()
#7 /var/www/html/web/core/lib/Drupal/Core/Render/Renderer.php(141): Drupal\Core\Render\Renderer->doRenderRoot()
#8 /var/www/html/web/core/lib/Drupal/Core/Render/Renderer.php(622): Drupal\Core\Render\Renderer->Drupal\Core\Render\{closure}()
#9 /var/www/html/web/core/lib/Drupal/Core/Render/Renderer.php(140): Drupal\Core\Render\Renderer->executeInRenderContext()
#10 /var/www/html/web/modules/contrib/canvas/src/ClientSideRepresentation.php(52): Drupal\Core\Render\Renderer->renderInIsolation()
#11 /var/www/html/web/modules/contrib/canvas/src/Controller/ApiConfigControllers.php(231): Drupal\canvas\ClientSideRepresentation->renderPreviewIfAny()
#12 /var/www/html/web/core/lib/Drupal/Core/Render/Renderer.php(622): Drupal\canvas\Controller\ApiConfigControllers->Drupal\canvas\Controller\{closure}()
#13 /var/www/html/web/modules/contrib/canvas/src/Controller/ApiConfigControllers.php(229): Drupal\Core\Render\Renderer->executeInRenderContext()
#14 /var/www/html/web/modules/contrib/canvas/src/Controller/ApiConfigControllers.php(241): Drupal\canvas\Controller\ApiConfigControllers->Drupal\canvas\Controller\{closure}()
#15 /var/www/html/web/modules/contrib/canvas/src/Controller/ApiConfigControllers.php(99): Drupal\canvas\Controller\ApiConfigControllers->normalize()
#16 [internal function]: Drupal\canvas\Controller\ApiConfigControllers->list()
#17 /var/www/html/web/core/lib/Drupal/Core/EventSubscriber/EarlyRenderingControllerWrapperSubscriber.php(123): call_user_func_array()
#18 /var/www/html/web/core/lib/Drupal/Core/Render/Renderer.php(622): Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}()
#19 /var/www/html/web/core/lib/Drupal/Core/EventSubscriber/EarlyRenderingControllerWrapperSubscriber.php(121): Drupal\Core\Render\Renderer->executeInRenderContext()
#20 /var/www/html/web/core/lib/Drupal/Core/EventSubscriber/EarlyRenderingControllerWrapperSubscriber.php(97): Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->wrapControllerExecutionInRenderContext()
#21 /var/www/html/vendor/symfony/http-kernel/HttpKernel.php(183): Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}()
#22 /var/www/html/vendor/symfony/http-kernel/HttpKernel.php(76): Symfony\Component\HttpKernel\HttpKernel->handleRaw()
#23 /var/www/html/web/core/lib/Drupal/Core/StackMiddleware/Session.php(53): Symfony\Component\HttpKernel\HttpKernel->handle()
#24 /var/www/html/web/core/lib/Drupal/Core/StackMiddleware/KernelPreHandle.php(48): Drupal\Core\StackMiddleware\Session->handle()
#25 /var/www/html/web/core/lib/Drupal/Core/StackMiddleware/ContentLength.php(28): Drupal\Core\StackMiddleware\KernelPreHandle->handle()
#26 /var/www/html/web/core/modules/big_pipe/src/StackMiddleware/ContentLength.php(32): Drupal\Core\StackMiddleware\ContentLength->handle()
#27 /var/www/html/web/core/modules/page_cache/src/StackMiddleware/PageCache.php(116): Drupal\big_pipe\StackMiddleware\ContentLength->handle()
#28 /var/www/html/web/core/modules/page_cache/src/StackMiddleware/PageCache.php(90): Drupal\page_cache\StackMiddleware\PageCache->pass()
#29 /var/www/html/web/core/lib/Drupal/Core/StackMiddleware/ReverseProxyMiddleware.php(48): Drupal\page_cache\StackMiddleware\PageCache->handle()
#30 /var/www/html/web/core/lib/Drupal/Core/StackMiddleware/NegotiationMiddleware.php(51): Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle()
#31 /var/www/html/web/core/lib/Drupal/Core/StackMiddleware/AjaxPageState.php(53): Drupal\Core\StackMiddleware\NegotiationMiddleware->handle()
#32 /var/www/html/web/core/lib/Drupal/Core/StackMiddleware/StackedHttpKernel.php(51): Drupal\Core\StackMiddleware\AjaxPageState->handle()
#33 /var/www/html/web/core/lib/Drupal/Core/DrupalKernel.php(715): Drupal\Core\StackMiddleware\StackedHttpKernel->handle()
#34 /var/www/html/web/index.php(19): Drupal\Core\DrupalKernel->handle()
#35 {main}

Proposed resolution

Show me the components!!

User interface changes